UPS failure modes (was: fire at NAC)

Bill Woodcock woody at
Thu May 29 18:23:30 UTC 2003

    > I had a little 2000VA rackmount Liebert UPS catch fire in 1997 and another
    > new and improved Liebert model almost catch fire about a year later.
    > What have others experienced as the failure mode(s) for their
    > UPS(s)?

We had a two-hour grid power outage here in Berkeley yesterday, during
which time our APC Symmetra 16kva fried two of its four batteries, and
went into bypass mode, which meant that the transition back from generator
to grid caused everything to reboot.  :-/

I've seen two previous APCs (both Matrixes) fry batteries...  The
batteries balloon up, and get really hot, and are too big to extract from
the chassis.  APC's solution to this is to have us take the entire UPS
offline for several days to completely dissipate the heat, and then try to
force the batteries out.  Since this seems to be an endemic problem, you'd
think they'd just design a chassis with somewhat more clearance around the
batteries so that failed ones could still be physically extracted.


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